- Physicochemical and thermal properties for a series of 1-alkyl-4-methyl-1, 2,4-triazolium bis(trifluoromethylsulfonyl)imide ionic liquids
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Physicochemical properties and long-term thermal stabilities are reported for a series of 1-alkyl-4-methyl-1,2,4-triazolium [NTf2] ionic liquids, and a Walden plot analysis was conducted in order to determine the ionicity of these materials. In general, viscosities were found to increase with increasing alkyl chain length while densities and molar conductivities were found to decrease. The 1,2,4-triazolium ionic liquids were classified as "good" ionic liquids after analysis of the Walden plot; however, they did not perform as well as the standard imidazolium ionic liquid [bmim][NTf 2]. Thermal properties from DSC and TGA experiments were also completed. 1,2,4-Triazolium ionic liquids with an alkyl chain length of octyl (C8) or less exhibited a single Tg transition below ?70 °C; however, the decyl (C10) and dodecyl (C12) systems exhibited a Tm value. No correlation between Tonset or Td5% and alkyl chain length was observed during short-term, temperature-ramped TGA experiments. However, long-term, isothermal TGA studies indicated a general increase in T0.01/10 value as the alkyl chain length increased. Both short- and long-term TGA studies indicated that the 1,2,4-triazolium ionic liquids were not as thermally stable as the model imidazolium ionic liquid [bmim][NTf 2].
- De La Hoz, Andreah T.,Brauer, Ulises G.,Miller, Kevin M.
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- POLAROGRAPHIC REDUCTION OF 1-SUBSTITUTED 1,2,4-TRIAZOLES
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The polarographic reduction of 1-substituted 1,2,4-triazoles in dimethylformamide (DMF) and acetonitrile was studied. 1-Methyl-, 1-ethyl-, and 1,2,4-triazoles are not reduced on a mercury electrode over the range of potentials accesible for polarography. 1-Phenyl-1,2,4-triazole and 1-vinyl-1,2,4-triazole are reduced in acetonitrile via a one-electron mechanism at high negative potentials.The reduction of 1-vinyl-1,2,4-triazole is accompanied by polymerization of the electrolysis products.A possible mechanism for the electrochemical reduction is discussed.
- Ermakova, T.G.,Gritsa, A.I.,Deriglazov, N.M.,Tatarova, L.A.,Keiko, V.V.,et al.
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- Silver complexes of 1,2,4-triazole derived N-heterocyclic carbenes: Synthesis, structure and reactivity studies
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Two silver(I) complexes {[1-R-4-(N-t-butylacetamido)-1,2,4-triazol-5- ylidene]2Ag}+ Cl- [R = Et (1b), i-Pr (2b)] of N/O-functionalized N-heterocyclic carbenes derived from 1,2,4-triazoles are reported. The silver complexes, 1b and 2b, have been synthesized from the reaction of the N/O-functionalized triazolium chloride salts namely, 1-R-4-(N-t-butylacetamido)-1,2,4-triazolium chloride [R = Et (1a), i-Pr (2a)] by treatment with Ag2O in 53-56% yield. The 1,2,4-triazolium chloride salts 1a and 2a were prepared by the alkylation reaction of 1-R-1,2,4-triazole (R = Et, i-Pr) with N-t-butyl-2-chloro acetamide in 47-63% yield. The molecular structures of the silver(I) complexes, 1b and 2b, have been determined by X-ray diffraction studies. The density functional theory studies on the silver 1b and 2b complexes suggest that the 1,2,4-triazole derived N-heterocyclic carbenes to be strong σ-donating ligands similar to the now much recognized imidazolebased N-heterocyclic carbenes. The reactivity studies with (SMe 2)AuCl and (SMe2)CuBr indicated the silver complexes, 1b and 2b, to be good transmetallating agents. Indian Academy of Sciences.
- Dash, Chandrakanta,Shaikh, Mobin M.,Ghosh, Prasenjit
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- Perfluorinated 1,2,3- and 1,2,4-Triazolium Ionic Liquids
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Dialkyl triazolium triflimides with perfluorinated side chains were prepared as hydrophobic ionic liquids (ILs) for surface impregnation. The key feature of the new materials are relatively short perfluorohexyl residues (nC6F13 = RF) as the fluorinated part of the cations, making the target compounds beneficial alternatives to established products because of their enhanced degradability and therefore lower bioaccumulativity. As heterocyclic scaffold, either 1,2,3-triazole or 1,2,4-triazole were chosen. As the two alkyl moieties, either two RFCH2CH2 groups or one RFCH2CH2 and one Et residue were applied. The diethyl congeners were also prepared. Fluorinated starting materials were RFCH2CH2OTf as alkylating reagent or RFCH2CH2N3 as 1,3-dipole for a copper catalyzed cycloaddition (CuAAC) with trimethylsilyl acetylene. After sequential CuAAC and alkylation reactions, the triflimide salts were finally obtained from the intermediate iodides or triflates with the aid of an ion exchange resin. Out of 14 triazolium salts prepared, four compounds have finally been identified as hydrophobic ILs (contact angles between 85° and 100° with mp. 100 °C), being promising materials for surface impregnation: the 1,2,3-triazolium triflate and triflimide with two fluorinated alkyl residues, and the 1,2,4-triazolium triflimides (two regioisomers) with one fluorinated alkyl residues and one ethyl group.
- Alpers, Torben,Muesmann, Thomas W. T.,Temme, Oliver,Christoffers, Jens
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- Taming Ambident Triazole Anions: Regioselective Ion Pairing Catalyzes Direct N-Alkylation with Atypical Regioselectivity
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Controlling the regioselectivity of ambident nucleophiles toward alkylating agents is a fundamental problem in heterocyclic chemistry. Unsubstituted triazoles are particularly challenging, often requiring inefficient stepwise protection-deprotection strategies and prefunctionalization protocols. Herein we report on the alkylation of archetypal ambident 1,2,4-triazole, 1,2,3-triazole, and their anions, analyzed by in situ 1H/19F NMR, kinetic modeling, diffusion-ordered NMR spectroscopy, X-ray crystallography, highly correlated coupled-cluster computations [CCSD(T)-F12, DF-LCCSD(T)-F12, DLPNO-CCSD(T)], and Marcus theory. The resulting mechanistic insights allow design of an organocatalytic methodology for ambident control in the direct N-alkylation of unsubstituted triazole anions. Amidinium and guanidinium receptors are shown to act as strongly coordinating phase-transfer organocatalysts, shuttling triazolate anions into solution. The intimate ion pairs formed in solution retain the reactivity of liberated triazole anions but, by virtue of highly regioselective ion pairing, exhibit alkylation selectivities that are completely inverted (1,2,4-triazole) or substantially enhanced (1,2,3-triazole) compared to the parent anions. The methodology allows direct access to 4-alkyl-1,2,4-triazoles (rr up to 94:6) and 1-alkyl-1,2,3-triazoles (rr up to 99:1) in one step. Regioselective ion pairing acts in effect as a noncovalent in situ protection mechanism, a concept that may have broader application in the control of ambident systems.
- Dale, Harvey J.A.,Hodges, George R.,Lloyd-Jones, Guy C.
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p. 7181 - 7193
(2019/05/10)
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- Hydrophobic spontaneous combustion N-hydrocarbonyl triazole dicyanoborane complex and preparation method thereof
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The invention relates to a hydrophobic spontaneous combustion N-hydrocarbonyl triazole dicyanoborane complex and a preparation method thereof. The structure of the N-hydrocarbonyl triazole dicyanoborane complex is shown as a formula I. The method for prep
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Paragraph 0027; 0030
(2018/09/21)
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- Correlating structure with thermal properties for a series of 1-alkyl-4-methyl-1,2,4-triazolium ionic liquids
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Thermal properties (Tm and Td) are reported for a series of 1-alkyl-4-methyl-1,2,4-triazolium ionic liquids where the alkyl chain length R and anion [X-] were varied. The highest melting transitions were observed when a lo
- Daily, Lucas A.,Miller, Kevin M.
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p. 4196 - 4201
(2013/06/04)
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- DEUTERIUM-MODIFIED TRIAZOLO-PYRIDAZINE DERIVATIVES AS GABA-A RECEPTOR MODULATORS
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This invention relates to deuterated substituted triazolo-pyridazines and pharmaceutically acceptable salts thereof. This invention also provides compositions comprising a compound of this invention and the use of such compositions in methods of treating diseases and conditions that are beneficially treated by administering an αl-GABAA receptor antagonist or an α2- and/or an α3-GABAA receptor partial agonist.
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Page/Page column 31-32
(2011/02/24)
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- 2-(PIPERIDIN-1-YL)-4-AZOLYL-THIAZOLE-5-CARBOXYLIC ACID DERIVATIVES AGAINST BACTERIAL INFECTIONS
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Compounds of formula (I) and their pharmaceutically acceptable salts are described. Processes for their preparation, pharmaceutical compositions containing them, their use as medicaments and their use in the treatment of bacterial infections are also described
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Page/Page column 85
(2010/07/02)
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- 7-(1,1-Dimethylethyl)-6-(2-ethyl-2H-1,2,4-triazol-3-ylmethoxy) -3-(2-fluorophenyl)-1,2,4-triazolo[4,3-b]pyridazine: A functionally selective γ-aminobutyric acidA (GABAA) α2/α3- subtype selective agonist that exhibits potent anxiolyti
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There is increasing evidence that compounds with selectivity for γ-aminobutyric acidA (GABAA) α2- and/or α3-subtypes may retain the desirable anxiolytic activity of nonselective benzodiazepines but possess an improved side effect pro
- Carling, Robert W.,Madin, Andrew,Guiblin, Alec,Russell, Michael G. N.,Moore, Kevin W.,Mitchinson, Andrew,Sohal, Bindi,Pike, Andrew,Cook, Susan M.,Ragan, Ian C.,McKernan, Ruth M.,Quirk, Kathleen,Ferris, Pushpinder,Marshall, George,Thompson, Sally Ann,Wafford, Keith A.,Dawson, Gerard R.,Atack, John R.,Harrison, Timothy,Castro, José L.,Street, Leslie J.
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p. 7089 - 7092
(2007/10/03)
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- Substituted triazolo-pyridazine derivative, pharmaceutical compositions made therefrom
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7-(1,1 -Dimethylethyl)-6-(2-ethyl-2H-1,2,4-triazol-3-ylmethoxy)-3-(2-fluorophenyl)-1,2,4-triazolo[4,3-b]pyridazine, and pharmaceutically acceptable salts thereof are selective ligands for GABAAreceptors useful in the treatment of disorders of t
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- An investigation into the alkylation of 1,2,4-triazole
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The alkylation of 1,2,4-triazole with 4-nitrobenzyl halides and a variety of bases afforded the 1- and 4-alkylated isomers with a consistent regioselectivity of 90:10. Previously reported regiospecific alkylations of 1,2,4-triazole were re-examined and the quoted isomer ratios were shown to depend on the isolation procedure. The use of DBU as base in the alkylation of 1,2,4-triazole allows for a convenient and high yielding synthesis of 1- substituted-1,2,4-triazoles. (C) 2000 Elsevier Science Ltd.
- Bulger, Paul G.,Cottrell, Ian F.,Cowden, Cameron J.,Davies, Antony J.,Dolling, Ulf-H.
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p. 1297 - 1301
(2007/10/03)
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- 1,2,3-Benzothiadiazole derivatives
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Novel 1,2,3-benzothiadiazole derivatives of the formula STR1 in which Het has the meanings set forth in the specification, and addition products thereof with an acid or metal salt are very effective for the control of undesired microorganisms. Novel intermediates of the formulae STR2 in which Het1 and R5 have the meanings given in the specification.
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- Chloropyridylcarbonyl derivatives
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Novel chloropyridylcarbonyl derivatives of the formula STR1 in which Het is STR2 n is 1 or 2, R1 is hydrogen, optionally substituted C1-6 alkyl, optionally substituted C2-6 alkenyl, optionally substituted C3-6 alkynyl, optionally substituted phenyl or optionally substituted pyrimidinyl, and R2 and R3, independently of each other, are hydrogen or C1-4 alkyl, and acid addition salts and metal salt complexes thereof, are outstandingly active as microbicides.
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- Solvation and nucleophilic reactivity of 1,2,4-triazolate ion in acetonitrile-methanol mixtures
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The 1,2,4-triazolate ion is a stronger hydrogen-bond accepting base than 5-substituted 1,2,3-benzotriazolate ions. Partly because of this characteristic, the transition-state anion of the 1,2,4-triazolate ion reaction with ethyl iodide indicates the most significant hydrogen-bond accepting basicity of a transition-state anion so far observed. The PM3 atomic charge on the nitrogen atom at the 4-position of the 1,2,4-triazolate ion and the average PM3 atomic charge on the nitrogen atom at the 1- and 3-positions of 5-substituted 1,2,3-benzotriazolate ions make the most significant contribution to the basicity of the relevant anion. The significant basicity for the transition-state anion has been rationalized through an empirical correlation between the specific interaction enthalpy, ΔtHAN→MeOHSI, and the PM3 atomic charge.
- Kondo, Yasuhiko,Yano, Kouji,Fang, Ossun,Saito, Hiromi,Takagi, Tatsuya
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p. 1827 - 1831
(2007/10/03)
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- Vinylation of 1,2,4-Triazole
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Reaction of 1,2,4-triazole with acetylene under pressure in the presence of potassium hydroxide and cuprous chloride was studied. The yield of 1-vinyl-1,2,4-triazole as a function of the nature of the catalyst and solvent and of the reaction conditions was considered. Physicochemical methods were used to show that the vinylation of 1,2,4-triazole with acetylene involves the N1 atom.
- Ermakova,Tatarova,Kuznetsova
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p. 805 - 807
(2007/10/03)
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- PREPARATION OF TRIAZOLYLMETHYLPHOSPHONATES AND OF TRIAZOLYLMETHYLPHOSPHONIUMSALTS AND THEIR APPLICATION IN THE WITTIG-HORNER REACTION
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The preparation of triazolylmethylphosphonates and of triazolylmethylphosphoniumsalts and their application in the Wittig-Horner reaction is reported.
- Maier, Ludwig,Kunz, Walter
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p. 201 - 204
(2007/10/02)
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